With this type of construction, there is a limit on the span length due to the capability of the gantry to span between the supports and also to take the dead weight of the deck with controlled deflection. However, spans in the range of 35 to 55 m are typical of this construction method.

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Advantages:●There is no need for false work to support the deck during casting in the spanned area.●The deck segments are cast in casting yard hence improving concrete quality control and formwork.●Work is repetitive resulting in manpower efficiency.●Continuous supply of segments hence speed of construction